<ARTICLE> 5 <PERIOD-TYPE> 6-MOS <FISCAL-YEAR-END> DEC-31-1997 <PERIOD-END> JUN-30-1997 <CASH> 95246447 <SECURITIES> 10445727 <RECEIVABLES> 19943096 <ALLOWANCES> 402812 <INVENTORY> 0 <CURRENT-ASSETS> 143547680 <PP&E> 112139862 <DEPRECIATION> 47879174 <TOTAL-ASSETS> 209487776 <CURRENT-LIABILITIES> 55615972 <BONDS> 0 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 300000 <OTHER-SE> 137723804 <TOTAL-LIABILITY-AND-EQUITY> 209487776 <SALES> 125268705 <TOTAL-REVENUES> 125268705 <CGS> 0 <TOTAL-COSTS> 104430558 <OTHER-EXPENSES> 0 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 0 <INCOME-PRETAX> 22789904 <INCOME-TAX> 8432267 <INCOME-CONTINUING> 14357637 <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> 14357637 <EPS-PRIMARY> .48 <EPS-DILUTED> .48